Choriocarcinoma is a malignant proliferation of the Langerhans cell and of syncytial cells of trophoblastic origin that is normally situated in the female genital tract after a gestational event such as molar pregnancy, term pregnancy, abortion, or ectopic pregnancy [1, 2].
Primary extragenital choriocarcinoma most often arises in the retroperitoneum, in the mediastinum, or intracranially. Although metastasis to the lung is not infrequent, PCC originating in the lung is extremely rare. The rarity of the occurrence of PPC and the small size of tumour samples make it challenging to diagnose either by cytology or bronchoscopic biopsy alone. The prognosis of extragonadal choriocarcinoma is usually poor, with various symptoms seriously affecting quality of life. Actually, resection followed by adjuvant chemotherapy appears to represent the best treatment for PCC of the lung [3]
In the present we firstly suspected a pregnancy in the light of high hCG value. Because all laboratory and diagnostic tests resulted to be negative, a chest CT scan was attended that showed the presence of lung mass within left lower lobe. Bronchoscopy showed no endobronchial lesion n and the results of bronchoalveolar lavage showed inflammatory cells without malignant characteristics [6–11]. The results of FNAB was suggestive for a lung cancer. Thus a standard lower left lobectomy was attended. Surprisingly, the histological results diagnosed the tumor to be a choriocarcinoma [1, 2]. In the present case, PCC of the lung was diagnosed after operation on the basis of the following observations: hCG fell dramatically after lobectomy: the lesion was limited to the lung, the patient's clinical course after surgery was uneventful, the ovaries, uterus and uterine tubes were found to be free of lesions on surgical removal, and no lesions were found in the digestive system.
Several explanations might be offered for this occurrence of PCC in the lung: origin from retained primordial germ cells that migrated abnormally during embryonic development; metastasis from a primary gonadal tumor that regressed spontaneously; or origin from trophoblastic emboli related to molar pregnancy after a long period of latency. Other reports support a hypothesis of dedifferentiation or metaplasia of nongonadal tissue such as primary lung cancer to trophoblast [1–3].
In closure, a positive hCG test result in patients with hemoptysis and progressive dyspnea could be diagnostic for a pulmonary choriocarcinoma and may be helpful for a early diagnosis. The diagnostic criteria would include lack of a previous gynecologic malignancy, solitary or predominant lung lesion with the exclusion of a gonadal primary site, raised serum hCG titers that become normal after surgery or chemotherapy, and pathologic confirmation of the disease